1. Institut National des Sciences Appliquées de Lyon – INSA Lyon
Centre d’Energétique et de Thermique de Lyon - CETHIL
1
Detailed description of the research work proposed at CETHIL
Title: Modeling for Scanning Thermal Microscopy applied to polymeric materials
Supervisors
Dr. Séverine GOMES, French National Center for Scientific Research (CNRS) researcher, CETHIL,
severine.gomes@insa-lyon.fr,
Tel: +33 (0)472436428
Dr. MhamedBOUTAOUS, AssistantProfessor,INSA Lyon,CETHIL,
mhamed.boutaous@insa-lyon.fr,
Tel:+33 (0)472436314
Dr. M. Boutaous (PhD Strasbourg, 1998), head of Thermal Sciences in Polymers group at CETHIL. His
skills concern the theoretical and experimental analysis of the interaction between processes and
polymer material thermomechanical behavior.
Localisation
Centre d’Energétique et de Thermique de Lyon (CETHIL, CNRS UMR 5008), Campus La Doua-
LyonTech, Villeurbanne (Lyon), France
Key words
Scanning Thermal microscopy, nanoscale thermophysical measurements, polymeric materials,
microstructure, nanotechnology, nanometrology
Context
This research project is in the framework of the development of Scanning Thermal Microscopy
(SThM) techniquesat CETHIL for the thermophysical characterization of new materials at micro and
nanoscales. Focus will be on polymeric materials.
The development of nanotechnologies and new nanomaterials is highly dependent on significant
advancesinthe fieldof metrology at the submicron scales. Different metrologies with high- spatial
and/ortemporal resolutionsare currentlyindevelopmentforthermal measurements. Among these
methods, Scanning Thermal Microscopy (SThM) is a technique that combines the ultra localized
analysisof surfacesallowedbyAtomic Force Microscopy and the measurement of temperature and
thermophysical properties by contact [1]. Breakthroughs are expected through this type of
metrology, particularly because the description of heat transfer is very different at the nanoscale:
thermal diffusion Fourier's law is rarely applicable, thermal radiation is different and convection is
poorly understood when the sizes involved are comparable to the one of the boundary layer. The
understandingof the thermal interactionbetweenthe probe andthe surface of the objectto analyze
isthe mainissue tocharacterize andinterpret rigorously the SThMmeasurement. As demonstrated
by previousworks,several heat transfer vectors determine this interaction: mechanical micro- and
nano- contact betweenthe tipandsample, meniscusof water adsorbed between the surface of the
tip and sample, the surrounding gas and radiation. The dependence of these mechanisms of heat
transferonthe geometryandthe size of the tip, the surface chemistry and other factors such as the
roughness of the surfaces is very poorly known. Therefore, the complexity of contact heat transfer
between the probe and the sample makes difficult the assessment of the performance of SThM
techniques, towards its thermal environment and the nature of samples, topography etc...

2. Institut National des Sciences Appliquées de Lyon – INSA Lyon
Centre d’Energétique et de Thermique de Lyon - CETHIL
2
Goals
The projectconcernsthe analysisof the linkbetweenmicrostructure and thermophysical properties
of polymericmaterials.The applicationof SThMto polymers involves non-normal conditions of use
of the method and requires developments in terms of multi-scale and physical modeling of the
probe-sample interaction. Thermomechanical modeling works will be crucial for a proper
interpretation of the measurement.
Various modeling have been already proposed in the scientific literature. This work aims:
- to establish a detailed analysis of these modeling,
- to identify the modeling the more adapted to the SThM silicon probe available (Thermal
lever from Anasys Instruments) in the laboratory,
- to improve the modeling of heat transfer at the tip-polymeric sample contact.
Reference:
[1] S. Gomès,A.Assy,andP.-O.Chapuis,Scanningthermal microscopy: A review, Phys. Status Solidi
A, 1–18 (2015) / DOI 10.1002/pssa.201400360.
Education / Competencies / Strengths
- The candidate (s) will have a degree in physics or engineering science. He (she) will be interested
by, not only experimental manipulations, but also the development of models in support of
experiments for their understanding.
- Mastering English.
- Mastering French would be a plus.